Ottmar Megenthaler, inventor of the Linotype machine, was born in Germany in 1854. He became a US citizen in 1878.

At the age of fourteen he started his apprenticeship as a watchmaker with his uncle, and studied at technical school at night. By the time he was seventeen he had completed his apprenticeship and had emigrated to America. He arrived in Washington D.C. in 1872 where he joined his cousin August Hahl, who had already opened a shop. A few years later they moved to Baltimore where they continued to make and repair watches and also make models for inventors who were required to supply models of their inventions when applying for a Patent. Mergenthaler joined Hahl's business as a partner in 1881.

Two court reporters approached Mergenthaler in 1876 to discuss a way of publishing legal briefs more quickly. There had been several attempts at desiging a machine that would simplify the process of composing and setting type used in printing presses. Mergenthaler began to design a machine that could form type moulds from papier-maché. This proved to be impractical.

By 1884, Mergenthaler had begun experimenting with metallic letter moulds to cast full lines of type. In 1886, Mergenthaler produced his first Linotype machine, which used copper matrices to mould column-width slugs of type. The first machine was installed at The New York Tribune and was used to compose the type for "The Tribune Book of Open Air Sports." The same year, Mergenthaler established his company the Merganthaler Linotype Co to market his new machine. The Linotype machine speeded up the printing process, reducing costs and enabling the expansion of printing and publishing.

Mergenthaler died in Baltimore in 1899.